1. Field of the Invention (Technical Field)
The present invention relates to fuel distribution and more particularly to a method and apparatus that prevents a wrong fuel product being dispensed into a storage tank.
2. Background Art
Presently there is a need for an apparatus or method to keep fuel tanker drivers from delivering the wrong fuel to a storage tank. Storage tanks are located in gas stations, truck stops, pipeline terminals, and refineries. Most storage tanks are underground, so it is impossible to visually determine what type of fuel the storage tank contains. Today most storage tanks are marked or color coded to alert the delivery person as to what type of fuel is contained within the tanks; however wrong deliveries still occur. In addition, delivery tankers have several compartments separated from each other to make it possible to transport different kinds of fuels at the same time such as gasoline and diesel. Due to the inattention of the driver, sometimes the driver unloads the wrong product into the wrong storage tank. When this happens, the intermixed fuel cannot be used because it will cause significant damage to any vehicle using the intermixed fuel. The same disastrous results occur with the use of the wrong fuel in a vehicle. In addition, an apparatus and/or method to prevent a wrong type of fuel from being dispensed from a holding tank to a vehicle tank are also necessary and can be accomplished with the present invention.
Several attempts have been made to solve a similar problem; however they are very complicated, costly, and require a separate power source for use. One of these prior art devices is discussed in U.S. Pat. No. 4,537,232. This device teaches an apparatus and method to disrupt the flow of the fluid upon detection of a nonconforming liquid. The device shuts down an electric pump, thus preventing the fluid from flowing. The device could not be used in an underground tank or down a filler hole and function completely on its own due to its size. The device needs electric wiring and power. It is designed to work on liquids that are pumped and are traveling upwards. Furthermore, it uses a two-step process; it shuts down a pump with an actuator, which in turn stops the flow. The device does not use the natural flow of the liquid to activate the flow-stopping feature.
Other prior art devices are disclosed in U.S. Pat. Nos. 4,632,139 and 4,865,070. Each of these devices separates liquids that are already mixed; they do not prevent mixing of unlike liquids. Further, they only work with liquids that do not mix with each other. The floating element in these devices is the actual stopper of the fluid and is not used to stop the flow of the wrong liquid down a filler tube or hole.
Other prior art devices use a floating device that sinks in a light liquid and floats in a dense liquid. The device is described in U.S. Pat. No. 4,537,232. However, as with other prior art devises, the stopping feature operates in one mode. For instance, they will only prevent a less dense fluid from flowing, but do not operate in a second mode; preventing a more dense fluid from flowing. The present invention operates in both modes. The floating device carries a prism to direct light to a photo electric cell or a magnet to disrupt electric power to stop a pump.
The present invention is a unique apparatus that prevents a wrong fluid from flowing, because fuels like gasoline and diesel mix very easily. The invention uses a one step process with no extraneous devices. It uses gravity to operate. The invention operates completely in a filler tube or down hole. It does not need electrical power, and it prevents the mixing of liquids that mix with each other. The invention activates a stopper that shuts down the flow of a liquid that flows by gravity.